1. Field of the Invention
The present invention relates to a remote control signal receiver for receiving remote control signals transmitted from a remote control signal transmitter, and to a remote control signal distinguishing method for the same. More particularly, the present invention relates to a remote control signal receiver capable of preventing incorrect recognition of remote control signals by detecting errors in received remote control signals, and to a remote control signal distinguishing method for the same.
2. Background Information
In conventional remote control signal transmission method in which a bit signal is detected based on a change in the logic level of a pulse signal, when an infrared remote control signal is received by an infrared receiver element that does not have very good reception performance, the remote control signal received by the infrared receive element is not always the same as the one transmitted from the remote control signal transmitter. Instead, the remote control signal as received by the infrared receive element sometimes includes distortions, whereby high- or low-level pulse signals that were in the remote control signal when it was transmitted from the remote control signal transmitter become lost. Accordingly, when some of the high- or low-level pulsed signals of a remote control signal are lost due to a distortion, the bit signals of the remote control signal are incorrectly recognized, causing the electronic device to malfunction.
As an example of such conventional arrangement, there has been known a remote control signal transmission method in which the rise signals and fall signals that indicate a change in the logic level of the received remote control signal are counted. The count is then compared with predetermined data that determine whether or not signals of the remote control signal fit into predetermined logic levels. A flip-flop is set or reset according to this comparison result. More specifically, if the received remote control signal includes abnormal data, which are data that do not fit into the predetermined logic levels, a reset signal is outputted from the flip-flop, but if the received remote control signal only includes normal data, which are data that fit into one of the predetermined logic levels, reception data and reception detection data are outputted. Japanese Laid-Open Patent Application H5-328451 discloses such remote control signal transmission method.
However, in such conventional arrangement, the error detection is performed by data processing hardware, rather than software. Therefore, the cost of installing such error detection function in a remote control signal receiver is high. It is also difficult to make modifications in such hardware-based error detection functions.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for improved remote control signal receiver and remote control signal distinguishing method that overcome the problems of the conventional art described above. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.